Part 1 specification – IAI America REXT User Manual
Page 210
![background image](/manuals/350365/210/background.png)
Part 1 Specification
Chapter 3 Gateway R unit
186
Part 1 Specification
[3] Parameter
Every time an instance is created, actual I/O memory addresses (or constants) must be set for data exchange with
input/output variables. These set addresses (or constants) are called parameters.
z
What is exchanged between the parameters and function block is the data of the size specified by the variable data
type. Take note that the parameter (address) information itself cannot be exchanged.
z
The I/O memory addresses that can be used as parameters are limited to CIO (channel I/Os), A (special auxiliary
relays), D (data memory), E (extended data memory), H (holding relays) and W (internal auxiliary relays).
Function block definition A
(example)
Algorithm
Variable definition
Input variables
a, c
Output variable b
Internal variable d
Program
Instance of function block definition A
Input source:
0.00
Input source:
3.00
Output source:
2.00
Input parameter
Output parameter
x
The value (I/O) in 0.00 is passed to a.
x
The value (I/O) in 3.00 is passed to c.
x
The value (I/O) in b is passed to 2.00.
-210-